Warped rear disc??

[fatnfast]

I think I would suspect the caliper also. As said, my pistons push back easily with 'thumb' pressure. Defo no need to slaken the bleed nipple. If the seals in the caliper are on the way out, this would give you the symptoms you describe. However, I guess a faulty master cylinder would also do this but less likely as its not exposed to the level of road crap etc that the caliper receives.

 

[ianboydsnr]

I think I would suspect the caliper also. As said, my pistons push back easily with 'thumb' pressure. Defo no need to slaken the bleed nipple. If the seals in the caliper are on the way out, this would give you the symptoms you describe. However, I guess a faulty master cylinder would also do this but less likely as its not exposed to the level of road crap etc that the caliper receives.

your wrong, needing to slacken the bleed nipples points to either the master cylinder or the brake lines, if the bleed nipples open but its still difficult to push the pistons back then that would point to the caliper seals

 

[fatnfast]

If you say so. My old Yam LC had the same dragging disc problem, with the piston difficult to retract with the nipple closed, which eased somewhat when I opened the bleed nipple. Stripping the caliper and fitting seals resolved the problem completely, but that was no doubt aided by the removal and replacement of 27 year old brake fluid! The master cylinder was fine. But....ian is also right in what he says, so ignore me!

 

[Francis]

OK, so E Bay came up trumps again with a caliper and mastercylinder for less than 20 quid. Once I get a chance I'll swap the caliper out and see if there's still a problem. Failing that then it's the mastercylinder with original caliper and see what that does. I'll let you know how I get on... Probably next weekend now, as I need it all this week to get to work.